Recently, as an alternative to a 4G cellular system represented by Long-Term Evolution (LTE) or the like, a 5G cellular system has come under consideration. In the 5G cellular system, a new wireless communication system is to be adopted in addition to LTE, and these two systems are to be used in combination. The new wireless communication system is to use a frequency band higher than that used for LTE in order to realize high-speed wireless communication.
However, in adopting a new wireless communication system to realize the 5G cellular system, a wireless communication device conforming to the 5G cellular system must include a function (circuit) conforming to LTE as well as a function (circuit) conforming to the new wireless communication system. This may lead to various inconveniences such as increases in the circuit scale (device size), the power consumption of the wireless communication device and the manufacturing cost of the wireless communication device.
Therefore, there are demands for a new technique which can resolve the above-described inconveniences.